Monitoring of contamination of raw milk with residual quantities of antibiotics

Abstract

Now in animal husbandry, more than 70 types of antibiotics are used, belonging to various groups. The most popular are longknown groups: penicillins, tetracyclines, fluoroquinolones, cephalosporins. The main reasons for the use of antibacterial agents are the presence of visible and latent pathologies in cows. Milk contaminated with antibiotics not only has significant restrictions on its use in processing, but also poses a serious threat to humans, as the end consumer of dairy products, as it provokes the development of antibiotic resistance. Laboratory studies were carried out on the basis of the Tyumen Regional Veterinary Laboratory in the Department of Microbiology, during 2019- 2020, the object of the study was 407 milk samples obtained from cows kept both in private farmsteads and in agricultural enterprises. It was found that 55.83% of raw milk samples delivered to the laboratory were contaminated with antibiotics. The most common antibiotic found in raw milk is amoxicillin (40.47% of all samples containing antibiotics), doxycycline (21.86%) was subdominant, erythromycin and azithromycin were encountered to a lesser extent (11.16% each), levofloxacin was encountered in 8.84% of milk samples with antibiotics, in rare cases the presence of streptomycin was recorded (6.51%). Most often, antibiotics were found in the summer. Thus, 54.42% of samples containing antibiotics were detected from June to August. Spring time accounted for 22.33% of all samples containing antibiotics. In autumn and winter, the proportion of samples with antibiotics was the smallest and amounted to 16.74 and 6.05%, respectively.